docstr: Convert proposal results to COCO json style.
docstr_tok: ["Convert","proposal","results","to","COCO","json","style","."]
code: def _proposal2json(self, results):
      """Convert proposal results to COCO json style."""
      json_results = []
      for idx in range(len(self)):
          img_id = self.img_ids[idx]
          bboxes = results[idx]
          for i in range(bboxes.shape[0]):
              data = dict()
              data["image_id"] = img_id
              data["bbox"] = self.xyxy2xywh(bboxes[i])
              data["score"] = float(bboxes[i][4])
              data["category_id"] = 1
              json_results.append(data)
      return json_results
  
imports: import itertools
  import logging
  import os.path
  import tempfile
  from collections import OrderedDict
  import mmcv
  import numpy
  from mmcv.utils import print_log
  from pycocotools.coco import COCO
  from pycocotools.cocoeval import COCOeval
  from terminaltables import AsciiTable
  from mmdet.core import eval_recalls
  from .builder import DATASETS
  from .custom import CustomDataset
label_desc: Use image node_id 7 for calling the CocoDataset obj's underlying member method code with example usage: obj._proposal2json(results) and returns: json_results